Nobelium preamp/DI

[bhcarpenter]

Build Rating

5.00 star(s)

My first tube project! I’ve used the Nobel preamp/DI live for the past year or so, so I was very interested to put this project from Conspiracy to Commit electronics together. I hear very little difference between the two and might actually prefer the Nobelium slightly.

It came together smoothly, using the BOM along with build tips from other projects on the C2C site. High voltages make me a bit nervous, but I didn’t even need to open up the back after powering it up for the first time.

Here it is being powered by the only supply I have right now that handles > 500mA, along with the obligatory gut shot.

If I can snag a current doubler adapter for my Strymon Zuma, this will probably be my rig for Christmas Eve service at church.

Killer job on this @vigilante398! Very easy to put together, and the faceplate is top notch. 5 stars

 

[vigilante398]

Looks great! Glad you're enjoying it!

 

[Harry Klippton]

second build complete. Fired right up. Tested the in/out today. Gonna try and test the xlr shortly. Third build is on my bench ready to go. Hopefully i will eventually be able to keep one. View attachment 64573

Kinda weird to post your build report in someone else's thread tbh

 

[Audandash]

That was my bad. I was on another thread in a differant window and didnt realize i came back to this one. Sorry bhcarpenter , I didn't mean to hijack. I have deleted.Thanks for pointing it out guys. I meant no disrespect.

 

[bhcarpenter]

I honestly don’t mind .

 

[danwojaz]

@bhcarpenter @vigilante398 what type of switches did you use? Is it on/on on on/off/on. Also for the transformer, I got the lightning boy audio one, for the orientation of the transformer matter ?

 

[vigilante398]

@bhcarpenter @vigilante398 what type of switches did you use? Is it on/on on on/off/on. Also for the transformer, I got the lightning boy audio one, for the orientation of the transformer matter ?

All switches are On/On.

Transformer orientation matters, the dot on the corner of the transformer needs to follow the dot in the corner of the PCB footprint.

 

[fmcc]

All switches are On/On.

Transformer orientation matters, the dot on the corner of the transformer needs to follow the dot in the corner of the PCB footprint.

Thanks, I'd been meaning to ask this question myself.

 

[chris.knudson]

Looks awesome. I just ordered mine - been waiting for the enclosures to come back in stock.

Is that 539mA just the Nobelium or is that the current of the whole board? Are you powering that with 9V or 12V? I'm already using one current doubler to power my HX Stomp. This might force me to rethink my power supply.

 

[danwojaz]

@vigilante398 Are the LEDs supposed to be flashing?

 

[vigilante398]

@vigilante398 Are the LEDs supposed to be flashing?

They are not. If the LEDs are flashing, it most likely means your power supply can't provide enough current for the pedal. What power supply are you using?

 

[danwojaz]

@vigilante398 Currently a 1 spot with 1200ma output

 

[danwojaz]

sorry 9v 1700mA output

 

[vigilante398]

@vigilante398 Currently a 1 spot with 1200ma output

That power supply should be more than sufficient for the circuit. If the LEDs flash quickly every 1-2 seconds and you're not getting signal through, the most likely cause is a short somewhere in the power section that's causing the circuit to try to pull more than 1700mA, which results in the power supply cycling on and off. It's common for supplies to have an over-current protection where they will cycle the power every second or two to check if the issue has resolved itself.

 

[danwojaz]

@vigilante398 Is there a schematic somewhere?

 

[vigilante398]

@vigilante398 Is there a schematic somewhere?

There is a schematic of the audio section in the actual Nobelium thread (this thread is a build report) here. The power section is the same as the power section of all my other projects.

 

[danwojaz]

@vigilante398 Hey, Thank you so much for all of your help. I spent several hours troubleshooting this, and I found my mistake. The LEDs I ordered were flashing LEDs. So they always flash.

 

[vigilante398]

@vigilante398 Hey, Thank you so much for all of your help. I spent several hours troubleshooting this, and I found my mistake. The LEDs I ordered were flashing LEDs. So they always flash.

Oh good, glad there was an easy explanation.

 

[danwojaz]

@vigilante398 I have an actual issue now. When it is powered on and nothing is plugged into the input, there is a high pitch noise I can adjust the frequency of with the treble and bass knobs. Then when I plug in and play, the noise goes away, but the low notes distort/ fart . I checked the voltage at R9 and it was 248V. What could be causing this noise?

 

[vigilante398]

@vigilante398 I have an actual issue now. When it is powered on and nothing is plugged into the input, there is a high pitch noise I can adjust the frequency of with the treble and bass knobs. Then when I plug in and play, the noise goes away, but the low notes distort/ fart . I checked the voltage at R9 and it was 248V. What could be causing this noise?

Please either start a troubleshooting thread or post questions to the main Nobelium thread. This thread is a build report.